1. Field of the Invention
This invention relates to devices used to tip vehicles to their sides while raising and exposing the under-surfaces of the vehicle and lowering and exposing the top surfaces, thereby making such surfaces accessible for inspection or work thereon.
2. State of the Art
The need for access to the undercarriage of a vehicle is well known. Often, for example, it is desirable to coat the entire undercarriage with a rust preventative coating. Sand blasting, painting and washing of vehicle undercarriages are desirable as maintenance procedures. Periodic maintenance requires that joints and couplings be frequently lubricated. Transmissions and differential units needing repair are often accessible only from beneath the vehicle and it is not uncommon that the oil in such units must be changed or that other servicing of the units is required. Other vehicle components such as starter motors, radiators, clutches, exhaust systems and fuel tanks, for example, may also have to be worked on from time to time and often are only accessible when the undercarriage is exposed.
In recent years the majority of new automobiles produced and sold have a unibody chassis, without an independent frame and for most of these vehicles it is only possible to remove the engine and transmission from the bottom of the vehicle, should that become necessary.
Government officials often need to inspect the undercarriages and tops of vehicles in locating illegal drugs and other contraband.
In general, the undercarriages of vehicles have been accessed either by sliding beneath a vehicle; positioning the vehicle over a pit in which a person may stand beneath the vehicle; or lifting the vehicle to a height that will allow a person to stand beneath the vehicle. Backyard mechanics frequently use a wheeled platform known as a creeper to propel them beneath a vehicle and it is not uncommon that the vehicle is supported by jacks and stands while the individual moves beneath on the creeper. Such an arrangement is often unsafe, since the jack(s) and support stands used may not provide adequate support and may allow the vehicle to drop. Dirt, oil, rust, paint, sand blasting particles, welding, slag, sparks from welding, gasoline and diesel fuel and even automotive parts invariably fall on a mechanic beneath the vehicle, with sometimes severe consequences to eyes and the like. Even professional mechanics may elect to use jacks and jack stands to perform a job when all available pits and/or hoists are occupied.
Pits are very permanent, expensive structures. Excavation of the pit is required and for safety purposes the pit walls must be made strong enough to prevent any possibility of collapse as a vehicle is driven and positioned over the pit. Once installed the pit cannot thereafter be moved for use at a different location and even tearing out and filling the pit can become a problem when the pit is no longer to be used. It is not uncommon that people are injured as a result of falls into open pits or that vehicles being driven onto tracks miss the tracks and fall into the pits. Furthermore, once the vehicle is driven onto tracks extending across a pit the tracks remain in place to obscure the view of and access to portions of the undercarriage.
Hoist and rack units that will allow a vehicle to be driven onto or over a rack that is then lifted by hydraulic cylinder retractable into a shop floor have also long been used. Such units are also essentially permanently installed, cannot be moved from location to location for use, and are very expensive to construct and install. They also provide permanent visual obstructions as well as preventing access to portions of the undercarriage. Permanently installed hoist and rack units are also costly to remove when it becomes necessary that this be accomplished.
More recently hoist and rack units have been developed that are less permanently installed. Such units may have four corner support posts and drive on ramps leading to support platforms, or vertically lifted and lowered platforms raised after the vehicle is positioned thereon. Other units have a pair of support legs connected by a top beam and support racks reciprocable on the legs to hold the vehicle in a balanced condition.
Even the newer hoist and rack units must be secured to a floor, or the like, so that they will have stability during use. These units also necessarily have components that will block vision and access by a user working beneath a vehicle. In addition, care must be taken when removing heavy components or adding heavy components to a vehicle on such units that adequate balance of the vehicle is maintained.
No matter what type of overhead support is used for a vehicle, a person working beneath and looking up is subject to neck fatigue resulting from bending the neck to look up and the holding of tools, part, etc. overhead. Back and arm fatigue can also occur.
A number of proposals have been made for apparatus that can be used to tilt a vehicle to its side so that the undercarriage is exposed. The advantage of such a unit is that it can usually be constructed at a lower cost than is associated with vertical lift hoists and, it can be made mobile and easily moved from location to location. However, all such apparatus, with which I am familiar, include lifting structure that must remain in place even after the vehicle is fully tilted and that will, like other structures previously described, obscure vision of and interfere with access to portions of the vehicle undercarriage.
It should also be apparent that with a side tilt unit no one must work beneath a vehicle. Accordingly, dirt, loose rust, oils, rust preventatives and other debris falls harmlessly, without dropping onto the worker. Also, there is no danger that the vehicle or pieces of the vehicle will fall onto a worker should support fail or should the worker or another party simply lose their grasp on a component. This, of course, is a constant danger to workers beneath a vehicle raised by a hoist, lift or jacks.
U.S. Pat. No. 1,288,138 discloses apparatus for tilting a vehicle to its side for servicing, or the like. As disclosed, the apparatus includes a pair of U-shaped cradles that will support a vehicle between them as the vehicle is turned to its side. U.S. Pat. No. 1,334,336 discloses a vehicle retaining frame structure with a curved sidewall. The frame is connected to an arm that supports a variable weight member. When the weight member has sufficient weight thereon the frame is tilted to place the vehicle on its side.
More recently structures have been developed to have arc-shaped support members that are attached, using special wheel lug bolts, to the hubs at one side of a vehicle. A force applied to the other side of the vehicle then rolls the vehicle to its side as it is supported on the arc-shaped support members. Such structures are shown, for example in U.S. Pat. Nos. 3,674,252, 4,579,505, 4,594,048 and 4,971,511.
U.S. Pat. No. 4,971,511 utilizes a hoist having a base shaft, a lifting shaft having one end pivotally mounted to one end of the base shaft, and a mast shaft having one of its ends pivotally mounted to the other end of the base shaft. The end of the lifting shaft not pivotally connected to the base shaft travels along the mast shaft under control of a powered hoist. The powered hoist comprises a winch fixed to the mast shaft and a cable wrapped around the winch and passing over a pulley system and having its running end fixed adjacent to the end of the lifting shaft that is guided along the mast shaft. With the lifting shaft extending beneath a vehicle such that the front wheels of the vehicle are at one side of the lifting shaft and the rear wheels of the vehicle at an opposite side of the lifting shaft, the attached end of the lifting shaft travels along the mast shaft to tilt or lower a vehicle having the wheels on one side of the vehicle connected to cradle members interconnected by a shaft to which the lifting shaft is pivotally attached, about the cradle members.
The apparatus disclosed in U.S. Pat. No. 4,971,511, while useful in many instances, has limitations and restrictions that reduce the overall usefulness of the device and its acceptability for vehicle tipping. It has been found, for example, that the mast shaft used must be in the neighborhood of eleven feet long. This makes the device impossible to use in a room having a ceiling that is less than eleven feet high. Consequently, the apparatus is not adaptable to use in most home garages and small commercial buildings. Furthermore, such length means that the apparatus is not readily transported in most pick-up trucks or vans.
As disclosed in the patent the cradle members are bolted to the wheels or hubs of the vehicle using special new lug nuts or bolts. It has been found, however, that the threads on even the new nuts or bolts often strip and release the cradle. Even if the nuts or bolts do not strip it is very time consuming to make the bolted attachment. Furthermore, each make and often each model of vehicle will have a different lug bolt pattern and may require different sizes or kinds of threads. As a result, considerable time is involved in bolting the cradles to or releasing the cradles from the lug bolts of a vehicle that is tipped. A standard six lug wheel requires the installation and removal of each nut or bolt four times. Thus, for each wheel there are twenty-four nut installations and removals. For both wheels, on one side of a vehicle, there are forty-eight nut or bolt installations and removals during a vehicle tilting procedure. This equates to thirty to forty-five minutes of the user's time per procedure.
None of the patents cited herein disclose a vehicle tilting apparatus designed to hold a vehicle in a tilted position even when the hoisting unit associated with the tilting apparatus is removed. Consequently, the prior art units will not allow convenient use in an automobile sales room, where it is desired that top and bottom of a vehicle be fully displayed. The cited prior art patents also fail to disclose strap on wheel rockers that are attached to wheels at one side of a vehicle and that will function with virtually any method of lifting the opposite side of the vehicle to position the vehicle in a side tilted position. The wheel rockers are constructed to maintain the tilted position and to permit movement of the tilted vehicle.
Principal objects of the present invention are to provide a "user friendly" side tipping apparatus for a wide variety of vehicles that is easy to operate by a single individual, that is reliable in use, that is fail safe and that is adaptable for use in a great many locations and for many purposes.
Principal features of the invention include spaced apart wheel rockers for use on the wheels at one side of a vehicle. Additional rockers may be used, as required, by the vehicle being tilted and the lifting structure and such rocker or rockers may be connected to a rocker bar extending between one or more rockers. A vehicle engagement apparatus is movable axially with respect to a base shaft for adjustable positioning against undercarriage components of the vehicle being tilted.
Each wheel rocker is secured to a wheel with straps and the wheel rocker may have at least one strap tightener thereon to facilitate locking of the rocker to the wheels. Guide bars may also be used with the straps, or independently, to position the wheel rockers to the wheels. A load distribution plate may be positioned between each wheel rocker and a wheel to which the rocker is attached if the size of the wheels is large enough to require such a distribution plate.
For use with trailers, a trailer ball receiving bar with a ball thereon is connected to a rocker which is interconnected by a rocker bar to other rockers being used.
Extension arms each have one end to be telescoped into fittings on the wheel rockers such that the entire assembly, including the vehicle can be moved using a dolly in the direction of the length of the vehicle, in a transverse direction or in a swinging pattern. The extension arms additionally cooperate with the rockers to maintain a fully tilted vehicle in position, when the lift mechanism is removed to provide unobstructed access to the vehicle undercarriage. The extension arms may have wheels or support plates affixed thereto or may have removable roller sets cooperating therewith to roll on floor plates placed over carpeting or the like.
In one preferred embodiment of the invention a support arm pivotally connected between the lower end of a movable mast shaft and intermediate the length of the base shaft provides support for the base arm as it is raised or lowered by power means carried by the mast. So arranged, the mast shaft follows the vehicle as the tilting proceeds. With the addition of extension arms to the wheel rockers, once a full ninety-degree plus tilt is achieved the base shaft support arm, base arm and mast shaft may be wheeled away and the user has unencumbered access to the entire undercarriage of the vehicle. This can be very important, for example, when the vehicle side tilting apparatus is used in a muffler replacement business and where different vehicles have the exhaust systems and mufflers located at different positions beneath the vehicles.
In another preferred embodiment of the invention the base shaft is pivotally connected intermediate its length to one end of a movable mast shaft. A support arm is pivotally connected at its opposite ends to power means carried by the mast shaft and to the base shaft near the end of the base shaft remote from the central rocker.
Extension arms are also provided that have flared ground engaging surfaces extending from the wheel rockers and roller sets attached to the extension arms. Extension arms extend from intersecting sockets on the wheel rockers and those extension arms extending in the direction of travel of the vehicle as it is tilted are angulated to provide ground engagement when the vehicle is fully tilted.
Additional objects and features of the invention will become apparent to those skilled in the art to which the invention pertains from the following detailed description and drawings.